In manufacturing a display device such as a plasma display and a liquid crystal display, it has been a practice to use spectral filters of various colors such as blue, green and red for spectrally classifying back light, etc. or to provide a black filter as a black matrix to enhance the contrast. To produce these color filters, use is made of photopolymerizable compositions for color filters containing various organic color pigments such as phthalocyanine pigments and azo pigments or light-screening pigments such as carbon black. Color filters are produced by applying the above-mentioned photopolymerizable compositions for color filters, which each has been preferably dissolved in a solvent, on substrates, and drying the same followed by pattern-making by photolithography.
In recent years, it has been desired to use plasma display devices (hereinafter referred to simply as "PDP") in practice. This is because PDPs are usable as displays having an emission luminance comparable to that of CRT displays and a relatively simple structure, which makes it possible to provide large-scaled PDPs and compact apparatuses. It is expected that PDPs provided with color filters of blue, green and red or a black matrix can show an enhanced contrast similar to that of CRT displays. However, the process for manufacturing PDPs includes the step of baking at a temperature of 350 to 750.degree. C. at which the conventional photopolymerizable compositions containing organic pigments or carbon black as the major components would undergo decomposition or volatilization of the pigments or carbon black. Thus, it is difficult to form any satisfactory color filters. To solve this problem, attempts have been made to add inorganic pigments to photopolymerizable compositions for color filters so as to impart heat resistance thereto. In these cases, however, there arises another problem that the photopolymerizable compositions containing inorganic pigments would gel within a short period of time, thus showing poor storage stability.